Retrofitting reinforced concrete beams by bolting steel plates to their sides. Part 2. Transverse interaction and rigid plastic design

In a companion paper, tests on bolted side plated beams have shown that sid e plates can substantially increase the strength of existing reinforced con crete beams with little if any loss of ductility and, furthermore, induce a gradual mode of failure after commencement of concrete crushing. However, it was also shown that transverse interaction between the side plates and t he reinforced concrete beam, that is vertical slip and which is a concept u nique to side plated beams, is detrimental. Transverse interaction increase s the forces on the bolt shear connectors and, hence, weakens the beam. It also reduces the ability of the composite plated beam to yield and, hence, to attain its full flexural capacity. The generic concept of transverse int eraction will be described in this paper and the results used to develop a new form of rigid plastic analysis for bolted side plated beams which is il lustrated with an application.